'''
作者: 沙昊
邮箱: shahao@zju.edu.cn
功能: 
包含算法: 
Copyright (c) 2023 by 沙昊, All Rights Reserved. 
'''
from re import X
import sys


def main(x,y,z):
    sha_days = 0
    sha_watered_days = 2

    while z>0:
        sha_days += 1
        z -= x

        if sha_watered_days >= 2:
            z -= y
            sha_watered_days = 0
        else:
            sha_watered_days += 1

    print(sha_days)


temp = input().split()
x = int(temp[0])
y = int(temp[1])
z = int(temp[2])

main(x,y,z)
 